1. Field of the Invention
This invention relates to devices having a radio transmitter with a coexistence controller, to corresponding methods of controlling transmissions, and to integrated circuits or software for carrying out such methods.
2. Discussion of the Related Art
It is known to provide radio links with automatically variable data rates. If the channel quality of the link changes owing to fading caused by movement or other changes in the air transmission path, this can be detected by a monitor and the data rate can be changed to suit or maximize the data transmissible over the link at the given time. It is also known to provide a coexistence control arranged to communicate with another radio transmitter suitable for part of another radio link, to control transmissions to enable both radio links to use potentially conflicting transmission frequencies.
Conflicts between wireless transmissions using the same frequency band are known. Conflicts can be very troublesome when the transmitters are very close to each other, e.g. a lap top computer with both a wireless Bluetooth and a “WiFi” (IEEE 802.11) transmitter operating in the same frequency band. One way to control such conflicts is to provide some form of coexistence etiquette which controls transmissions so as to reduce the problem.